1. Field
Example embodiments relate to a target material and a method of manufacturing a semiconductor device using the same, and more particularly, to an oxide semiconductor target and a method of forming the same, a method of forming an oxide semiconductor layer using the same and a method of manufacturing a semiconductor device using the same.
2. Description of Related Art
Oxides including Zn or In, for example, ZnO, InGaZnO4, Zn—In—O, or Zn—Sn—O, may have a mobility of 10 to 100 times greater than amorphous silicon.
Also, the oxides may show good semiconductor characteristics, that is, they may have an on/off current ratio (Ion/Ioff ratio) of 105 to 107. Also, since the oxides have a large band gap of 3.2 to 3.4 eV, they may have small leakage current due to visible light.
Hereinafter, oxides that include Zn, In, Ga, Sn, or a composite of these materials will be referred to as oxide semiconductors.
An oxide semiconductor layer formed of the oxide semiconductor may be formed using an RF sputtering method, a pulsed laser deposition method, a molecular-beam epitaxy method, or a metal organic chemical vapor deposition method.
However, when the above methods are applied to LCD panels that use large glass substrates, the productivity of the LCD panels may be reduced due to very slow deposition rate of the oxide semiconductor layer and the difficulty of ensuring uniformity of the oxide semiconductor layer.
Currently in the LCD industry, oxide semiconductor layers, for example, ZnO layers, In2O3 layers, Ga2O3 layers, Hf—In—Zn—O layers, Zn—In—O layers, Zn—Sn—O layers, or Ga—In—Zn—O layers are mainly deposited using an RF magnetron sputter method.
However, when the oxide semiconductor layers are formed using the RF magnetron sputter method, the deposition rate of the oxide semiconductor layers may be lower than that of an amorphous silicon film.
The oxide semiconductor layers may be formed using an oxygen reactive DC sputter method in which a pure metal alloy that includes at least one of In, Ga, Zn, and Sn may be used as a target and oxygen gas may be supplied during the deposition.
However, in this method, the pure metal alloy used as a target may be brittle, and it is difficult to control the composition of the oxide semiconductor layer since the composition change at the surface of the oxide semiconductor layer may be severe due to the addition of oxygen. Accordingly, it may be difficult to apply the oxygen reactive DC sputter method to deposit the oxide semiconductor layer on a large glass substrate.